Table 3.

Demographics of pregnant women with group B streptococcus infection, with and without a history of penicillin allergy, who delivered between 2009 and 2014

Demographic characteristic	History of penicillin allergy	No history of penicillin allergy	p value
Age, years, mean (SD)	30.28 (5.64)	29.66 (5.79)	< 0.0001
Total deliveriesa	3500	39,024
Number of unique women	3245	36,153
Active drug class allergies before delivery, mean (SD)	1.485 (0.832)	0.647 (0.570)	< 0.0001
Number of live births	3545	39,571
Cesarean deliveries, no. (%)	1063 (30.37)	10,757 (27.57)	0.0004
Total days in hospital from the date of initial admission for delivery to 6 months after delivery for women, mean (SD)	3.55 (1.51)	3.46 (2.00)	0.002
Total days in hospital from the date of initial admission for delivery to 6 months after delivery for women with spontaneous vaginal delivery, mean (SD)	3.201 (1.14)b	3.147 (1.48)c	0.0304
Total days in hospital from the date delivery to 6 months after delivery for the infants, mean (CI)	4.05 (3.77–4.33)	3.85 (3.78–3.91)
Antibiotic exposure ± 3 days from delivery, no. (%)	3392 (96.91)	37,757 (96.75)	0.606
Total antibiotic courses	6726	95,522	< 0.0001d
Total new drug-class allergies within 30 days of peripartum antibiotic exposures, mean (CI)	0.0269 (0.0211–0.0326)	0.0011 (0.0008–0.0015)
New Clostridium difficile infections within 90 days of delivery, no. (%)	0 (0.00)	20 (0.05)	0.4037

^aA woman may have multiple deliveries during the study interval, and each delivery is counted as an independent event. All descriptive statistics and statistical tests are at delivery level, not patient level.

^bn = 2437 women.

^cn = 28,267 women.

^dp value for testing whether the mean number of courses of antibiotic is different for those with penicillin allergy from those without penicillin allergy (among those exposed).

CI = confidence interval; SD = standard deviation.